1) Field of the Invention
The invention relates to a device for separating a flowing fluid into at least two fractions with differing mass density, comprising: a main tube substantially in the form of a cylinder jacket and having an infeed opening and an outfeed opening located at the opposite outer end; a first swirl element arranged in the main tube in the vicinity of the infeed opening for imparting a rotating movement to the fluid flowing through the main tube; a first auxiliary tube placed concentrically in the main tube at a distance from the first swirl element and leading to the outfeed opening of the main tube; and first discharge means connecting to the jacket of the main tube for discharging a heavier fraction of the fluid. The rotating movement is imparted to the flowing fluid by means of a swirl element which is usually provided with a plurality of blades, the vane angle of which increases in the flow direction.
2) Description of the Prior Art
Such a separating device is known from U.S. Pat. No. 3,641,745 and from U.S. Pat. No. 4,478,712.
In the prior art according U.S. Pat. No. 3,641,745 a device is disclosed for separating into fractions a gas-liquid mixture in at least two fractions (see title). The device comprises a cylindrical main tube provided with an inlet and an outlet located on the opposite end walls of the main tube. In the main tube close to the inlet a first swirl element (deflector with vanes) is located to make the fluid to be separated swirl. The device is also provided with an additional tube located coaxial in the main tube on a distance of the first swirl element, which additional tube leads to the outlet of the main tube. On the shell of the main tube connect outlet means that lead in a vertical direction for leading a heavier fraction of the fluid away. In the additional tube a second swirl element is located to impart to the additional tube flowing fluid a swirling movement. The outlet shaped as a tube may be considered as a second additional tube that connects coaxial to and in a distance of the second swirl element. On the shell of the first additional tube connect second outlet means for leading away a heavier fraction if the fluid (perforations in the connection to the drain).
It is noted by the way that U.S. Pat. No. 4,299,611 also shows a separating device provided with two separating members. This is however a separating device for removing or filtering particular material from an airflow, and not a device for separating random fluids, more particularly for separating a liquid and a gas fraction. Although the advantages of the invention are manifest with fluids of random nature, an important field of application for the invention lies in the separation of a lighter fraction of the fluid substantially comprising gas from a heavier fraction of the fluid substantially comprising liquid.
The object of the invention is to provide a device which provides for a better separation.